Method for making wire protector

ABSTRACT

A method for making a wire protector comprising a steel tube rolled from a flat sheet that has had a plurality of dimples formed adjacent one edge which will become an axial end of the tube. The tube is cylindrical and of an external diameter closely to fit a hole bored in a stud of a mobile home or recreational vehicle. The dimples protrude from the exterior and when the wire protector is hammered into the hole of the stud, the dimples grip the stud and additionally cause slight contraction of the tube forcing the seam tightly closed.

United States Patent Baillie Dec. 16, 1975 METHOD FOR MAKING WIRE2,244,975 6/1941 Tinnerman 85/5 PROTECTOR [75] Inventor: William R.Baillie, Hoffman Estates, Primary E.\'an1iner-Lowell A Larson lll.Attornqr. Agent, or Firm-Silverman & Cass, Ltd. [73] Assignee: BlueRibbon Industries, Inc.,

Arlington Heights lll. [57] ABSTRACT [22] Filed: Aug. 12, 1974 A methodfor making a wire protector comprising a 7 App! 496760 steel tube rolledfrom a flat sheet that has had a plu- Related US. Application Datarality of dimples formed adjacent one edge which will 2 Division of Sch341476 March 15 [973 PM become an axial end of the tube. The tube iscylindri- 31451413v cal and of an external diameter closely to fit ahole bored in a stud of a mobile home or recreational vehi [52] US. Cl.72/368 The dimples protrude from the exterior and when 51 Int. Cl. .4B21D 51/10 the wire protector is hammered into the hole Of the 581 Fieldof Search 85/5; 29/525; 72/368 Studw the dimples g p the Stud andadditionally Cause slight contraction of the tube forcing the seamtightly References Cited closed.

UNITED STATES PATENTS Y 2 Claims, 5 Drawing Figures 1,344.59: 6/1920Schacfcr 85/5 US. Patent Dec. 16, 1975 3,926,030

METHOD FOR MAKING WIRE PROTECTOR This is a division of application Ser.No. 341,476 filed Mar. 15, 1973, now US. Pat. No. 3,855,413.

BACKGROUND OF THE INVENTION The invention relates to wire protectorsused in mobile homes and recreational vehicles. The purpose of the wireprotector is to form a shield or sheath for wires passing through woodenmembers such as studs, risers and beams. An important need for wireprotectors is to prevent wiring from being pierced by nails, screws orother fasteners used by the occupant. With space at such a premium invehicles of this type, the chances of some fastener being driven intothe wire are increased, especially since supporting structures even oflight weight preferably are mounted to studs and the like members.

Wire protectors of this general nature are known. One type consists of acylindrical tube having its seam welded and provided with a flare at oneend thereof. The end opposite to the flare is placed at the entrance ofthe hole and the protector driven fully into the hole. Although this isan effective wire protector it is very expensive to manufacture.

Another type of wire protector consists of a simple rectangular sheet ofsteel rolled to provide an open tapering seam. The narrower end of theseam is placed in the drilled hole and the wire protector driven home.The purpose of the tapered seam is to provide leeway for the holecausing the end being hammered to be forced to contract. The theory isthat this will tightly hold the wire protector within the hole.

The problem with the latter type of wire protector is not only thatthere is a tendency for the protector to shake loose as the wood driesand the vehicle is subjected to vibration, but additionally, theinstaller must be careful to face the seam downwardly since it does nottightly close. In any other location the seam could provide a -guide forthe entrance of a nail or screw which could pierce the wires passingthrough the protector.

The invention is directed to a highly economical wire protector whichdoes not require orienting when installed and which gives maximumprotection against the wires being pierced. The disadvantages of theprior art are obviated as will be explained hereinafter.

SUMMARY OF THE INVENTION A method for making a wire protector comprisinga cylindrical tubular method formed of a single rectangular member ofsheet steel and having a closed seam. Protruding dimples are providedcircumferentially spaced adjacent one axial end of the wire protectorand serving to substantially lock the wire protector into a wooden studor the like. The protector is adapted to be driven into a predrilledhole in the stud.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view of a wireprotector constructed in accordance with the invention;

FIG. 2 is a sectional view taken through the wire protector along theline 22 of FIG. 1 and in the indicated direction;

FIG. 3 is a view similar to that of FIG. 2 but showing a modified formof the invention;

FIG. 4 is a sectional view taken through a structural member of a mobilehome or the like having the wire protector of the invention installedtherein and wires being shown traversing the wire protector; and

FIG. 5 is a developed view of a steel blank suitable for fonning thewire protector of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Generally, as previouslyexplained, the invention relates to a wire protector for mobile homesand recreational vehicles. Specifically, the wire protector serves as ashield or sheath passing through a structural member so that wires maybe pulled through the member and be protected.

The wire protector of the invention is designated generally by thereference character 10 and the same comprises an elongate steelcylindrical tube 12 formed of sheeting suitably rolled or otherwiseoperated upon.

The bore 14 of the wire protector 10 provides a passageway 14 to enablewires to be pulled through the same as will be explained in connectionwith FIG. 4. A plurality of dimples or protrusions 16 is formed in thetube 12 in any suitable manner, such as, for example, by upsetting thematerial in punching shallow recesses 17 into the interior of the wall12. These protrusions 16 are preferably spaced circumferentially aroundthe periphery of the tube 12 and are located adjacent one axial end 20.For example, the distance from the center of the protrusions 16 and theend 20 in a commercial version was three-eighths of an inch.

When the body 12 is formed either in a rolling process or in suitabledies or fixtures using punch press techniques, the resulting abuttingends 22 and 24 (see FIG. 5) of the blank 26 from which the wireprotector 10 is formed will tightly engage to provide an axiallyextending seam 28. In the fabrication, this seam is closed as shown inFIGS. 2 and 3. Since techniques may vary, the abutting ends 22 and 24may not in certain instances be perfectly arcuate as shown in the wireprotector 10 of FIG. 3. This is a variation of the structure of theinvention that does not adversely affect its efficiency and operation.The resulting seam is shown at 28.

In use, a hole 30 having the same diameter as the wire protector 10 or10 is drilled in a wooden structural member such as shown at 32 in FIG.4. For example, the hole 30 is drilled three-quarters of an inch indiame ter and the wire protector 10 or 10 has an outer diameter ofthree-quarters of an inch. The axial end 34 opposite the end 20 isinserted into the hole and the end 20 is struck with a hammer, drivingthe wire protector 10 or 10' fully into the hole. The wire protector ispreferably the same length as the width of the structural member. Forexample, in ceilings where l X 4s or 1 X 65 are used as stringers, thefinished lumber thickness is three-quarters of an inch. The length of awire protector for this type of installation would be approximatelythree-quarters of an inch. Thus, wire protectors one and five-eightsinch long would be suitable to pass through 2 X 4s and wire protectorsapproximately three and one-half inches long would be suitable where astud is formed of a double thickness of 2 X 4s.

When the wire protector has been driven into the hole, if the end 20 isslightly peened as shown at 36 in FIG. 4, it does not adversely affectthe installation. When the dimples or protrusions 16 engage the walls ofthe hole 30 two things occur. In the first place they exert aconstricting pressure on the wire protector tending to more tightlyclose the seam 28, thereby giving additional protection against entry bya nail or screw. The second thing that occurs is that the wood adjacentthe entrance to the hole 30 is compressed slightly as the protrusions 16enter. The paths of these protrusions are indicated by the dotted lines38 in FIG. 4. Since wood generally is of a quasi-plastic nature, thegrooves formed by the protrusions will tend to regain their originalconfiguration thereby closing. The protrusions 16 are deliberatelyformed to be rounded so as not to tear the fibers of the structuralmember 32. After a period of time when the wood has recovered, the wireprotector 10 or 10 will substantially be locked in place so thatvibration will not be able to dislodge the same.

In FIG. 4 several wires are shown at 40 passing through the passageway14.

In the manufacture of the wire protector 10 or 10, the same is rolledfrom a blank 26 which, as shown, is a rectangular piece of sheet steel.The long edges 20 and 34 will provide the leading and trailing endsrespectively of the wire protector when the blank 26 is rolled into thetube 12. The ends 22 and 24 will be abutting as explained. Prior to therolling process, the recesses 17 are punched or upset on the inside ofthe blank 26 thereby forming the protrusions 16. As

shown, there are four such protrusions 16 on the versions 10 and 10' ofthe invention but more or less of such protrusions may be used.

In the commercial version of the wire protector, a common grade ofcold-rolled sheet steel one-sixteenth of an inch in thickness was used,the resulting structure meeting all of the requirements of mobile homeand recreational vehicle codes established by regulatory agencies havingjurisdiction over the construction of such mobile homes and recreationalvehicles.

In the fabrication of the cylindrical body 12 the individual wireprotectors may be formed from individual blanks like rectangular sheetsteel blank 26 or in a progressive die arrangement from a strip in whichthe blanks are cut from the strip before or during the rollingoperation. In either event, prior to forming the tubular body 12 therecesses 17 are punched so that the tools, dies, or fixtures which areused must accommodate the protrusions 16 if such protrusions are engagedduring the rolling process.

Some variations in the details of the structure of the invention arecapable of being made without departing from the spirit or scope of theinvention as defined in the appended claims. For example, while it ispreferred that the protrusion 16 be located adjacent one axial end ofthe body 12, they could be elsewhere and likewise there could be morethan one row of the same.

What it is desired to secure by Letters Patent in the United States is:

1. A method of making a wire protector of sheet steel which comprisesforming a rectangular blank of sheet steel and punching recesses in onesurface on a line parallel with a pair of opposite edges of said blanksimultaneously producing surface protrusions on the opposite surface ofsaid blank, and roll forming the blank into a hollow cylindrical tube sothat the two other opposite edges are tightly abutting in a seam, theprotrusions being unaffected by the rolling and defining acircumferential line on the exterior of said tube, the recesses beingpunched prior to forming of the tubular body.

2. A method as claimed in claim 1 in which the surface protrusions arerounded.

1. A method of making a wire protector of sheet steel which comprisesforming a rectangular blank of sheet steel and punching recesses in onesurface on a line parallel with a pair of opposite edges of said blanksimultaneously producing surface protrusions on the opposite surface ofsaid blank, and roll forming the blank into a hollow cylindrical tube sothat the two other opposite edges are tightly abutting in a seam, theprotrusions being unaffected by the rolling and defining acircumferential line on the exterior of said tube, the recesses beingpunched prior to forming of the tubular body.
 2. A method as claimed inclaim 1 in which the surface protrusions are rounded.